I have no idea if the magic keeping it together is stronger than the magic keeping the plate from being damaged. I am guessing it isn’t. Even if it is or is close, the benefit of removing the piece outweighs the cost of the endeavour. I think you are overestimating the force acquired from just swinging something compared to the force Shardplate just inately has. The force behind the hook isn’t from the hook, nor from a swing, it’d be from the main-strength in the Shardplate the guy is wearing. I am specifically talking about a fight between Shardplate wearing contestants.